The most entitled person to a child's custody if the father is non-Muslim

Q: I am a Muslim woman from Sweden. I write to you about a complex problem that befell me. Before I embraced Islam, I had been married to a non-Muslim man and gave birth to a child. I named him Mustafa. I and Mustafa's father separated. Mustafa's father wanted to raise the child. I feared that Mustafa's father might use the religion for his own sake. So, I suggested that I sign an agreement with Mustafa's father without the interference of the court. This agreement stipulates that:1- Mustafa's father has the right to see his son for a certain period of time every year.2- Mustafa's father abides by respecting the traditions of Islam and never opposes the teachings set by Mustafa's mother with regard to the rules of food and drink. (Part No. 21; Page No. 196) Now, let me narrate the story of my problem. I want to relate my problem in details to let you understand the case: when I accepted Islam, my mother was not happy and she hoped that I might forget the whole matter after a while. Some months later, I got married to a Muslim man, a matter that led my mother into a state of hysteria. As a result, she kidnapped Mustafa and called Mustafa's father as well as the police and the social security. She told them falsehoods about me and my husband. She contacted the lawyer of Mustafa's father and tried to get us out of our flat. She wrote a letter to the lawyer of Mustafa's father and told him some lies about me and that I am not competent to raise Mustafa. She added that I am completely insane. In Sweden, the individuals have the right to embrace the religion they want, but it is natural that such case does not apply to the religion of Islam. I was very worried that I might lose Mustafa. When I signed the agreement with Mustafa's father, I had the intention not to let him see Mustafa at all. I hoped to leave this country in the near future and get rid of this problem completely. Unfortunately, my husband does not yet have a residence document. This means that he can not get a Swedish passport, so we can not travel to any place. Cooperating with Mustafa's father, my parents helped him with money and securing several things. They (Part No. 21; Page No. 197) all do whatever they can against me and against Islam. I know that they intend to influence Mustafa to leave Islam in the same way they did with me. They did several things against me and my family, which I find no room or time to relate in this letter. Now, let me ask the following questions:1- Is it permissible for me to breach the agreement I signed with Mustafa's father out of my fear so that Mustafa could live in peace?2- Is it permissible for me to prevent Mustafa's father from seeing his child?3- Is it permissible for me to send Mustafa to another country?4- Is it permissible for me in such case to travel alone? Or will I be in need of a Mahram (spouse or permanently unmarriageable relative) to travel with me?5- Do my parents have the legal right to see their grandson even though they are non-Muslims and plot against Islam? 6- Should I pay a visit to my mother despite the hostility she holds against me?I am very worried about Mustafa as this may cause him internal conflicts. Two months ago, Mustafa began to study at an Islamic school in Malmo He goes there everyday to learn the Holy Qur'an. He loves his school and classmates. Though he is Swedish, he speaks Arabic better than the Arab children themselves. He has memorized several Surahs (Qur'anic chapters). (Part No. 21; Page No. 198) All Praise be to Allah that my son is very intelligent. However, I am always worried about him as I fear that his father may affect him and distract him from the Right Path of Islam, as his father is bad-tempered. I know that he is a liar when he says he respects my religion. This situation is not suitable for a child of this age. I am an adult and reasonable woman who feels strong through this religion. In addition, I can protect myself, but the child can not protect himself. It is not logical or permissible in the field of Islamic education for Mustafa to see his mother performing Salah (Prayer) and reciting the Holy Qur'an one day and see his father performing acts of Kufr (Disbelief) the next day. Mustafa may be inflicted with disorders, which may lead him to be unable to distinguish between what is right and what is wrong. I would be grateful if you would give a reply to my letter as quickly as possible. This is because I want to do what I can for Mustafa and his future so that he can be a pious Muslim, In-Shaa` Allah. I would like you to give me the ruling on the following question: Is it permissible for me in Islam to keep Mustafa away from his father who is a non-Muslim (a disbeliever)?